Lubricating oil compositions and fireresistant lubricating emulsions produced therefrm



United States Patent M 3,108,070 LUBRHCATKNG GIL CGMPCSHTIQNS AND FIRE- RESESTANT LUBRECATHNG EMULSIQNS PRO- DUCED THEREFRGM Hamid A. Hartnng, Collingswood, Ni, and Edward Barhis, Philarleiphia, ha assignors to The Atlantic Refining Company, Phiiadeiphia, Pa a corporation of Pennsylvania No Drawing. Filed Aug. 8, 1960, Ser. No. 47,903 12 Claims. (Ci. 252-317) This invention relates to lubricating oil compositions,

and more particularly, to lubricating oil compositions which can be used to produce water-in-oil emulsions. In a more specific aspect, the invention relates to fireresistant hydraulic fluids. This application is a continuation-in-part of our copending application Serial No. 838,415, filed September 8, 1959, entitled Lubricating Oil Compositions and Fire-Resistant Lubricating Emulsions Produced Therefrom.

Petroleum oils are extensively used for the lubrication of many types of machinery, as a base for lubricating greases, and in the preparation of hydraulic or power transmission fluids. Under certain conditions, however, their use is restricted because of their lack of fire resistance. For example, it has been found necessary to develop expensive fire-resistant synthetic oils for use in the hydraulic systems of aircraft because of the inherent fire hazard attending the use of hydrocarbon oils in such systems. Similarly, it has been found necessary to develop fire-resistant oils for use in lubricating mining machinery and in the hydraulic systems employed in mines to operate mining machinery since sparking and electric arcs are often encountered in mining operations. Consequently, fire-resistant lubricants and hydraulic oils are needed to reduce the fire hazard. in many similar situations fire-resistant lubricants are required which heretofore has prohibited the use of petroleum oils.

A petroleum lubricating oil composition now has been found which can be emulsified with water to produce highly stable water-in-oil emulsions having excellent fire resistance While retaining the high quality lubrication properties of a petroleum lubricating oil.

It is an object of this invention to provide a lubricating oil composition which can be used to produce water-inoil emulsions.

it is another object of this invention to provide a lubricating oil composition which can be used to produce stable, fire-resistant water-in-oil lubricating emulsions.

It is another object of this invention to provide stable fire-resistant water-in-oil emulsions having superior lubrication characteristics.

It is another object of this invention to provide a hydraulic fluid having superior fire-resistance and lubrica tion characteristics.

Other objects of this invention will be apparent from the following description of the invention and the appended claims.

In accordance with this invention a combination of certain emulsification agents has been found which, when introduced into a high quality solvent refined petroleum lubricating oil will permit the formation with water of water-in-oil emulsions over a wide range of water content. For example, with the emulsification agents of this invention, it is possible to produce Water-in-oil emulsions containing as little as percent by weight of water to as much as 95 percent by weight of water.

Water-in-oil emulsions have been produced heretofore from petroleum oils, but such compositions were either incapable of containing more than small amounts of water, generally less than 40 percent by weight, or were unstable. In those instances when unstable emulsions ilhhfiih Patented ct. 22, l63

were produced, the emulsions either broke or invetted, i.e., the phases separated or the water became the continuous phase and the oil the dispersed phase. if either of these conditions arose the resulting composition was entirely unsuitable as a lubricant.

The lubricating composition of the instant invention not only permits a wide range of water content in the water-in-oil emulsion produced from it, but it also provides a very stable emulsion having excellent lubrication characteristics. This stability is obtained by combining two emulsification agents so that the resultant combination has the proper balance of hydrophobic and hydrophilic properties. This balance is obtained by combining an agent which is an exceedingly efiicient water-in-oil emulsifying agent with an agent which is a less efficient water-in-oil emulsifier. It has been found, however, that only certain specific compounds having these emulsification properties may be combined to give the described balance between hydrophobic and hydrophilic properties and, in addition, give an emulsion in which the droplets of water forming the dispersed phase are extremely small. Small and uniform particle or droplet size is necessary to obtain a stable emulsion and to provide an emulsion of superior lubrication characteristics.

The highly efficient water-in-oil emulsifying agent suitable for this invention is an ester-containing reaction product produced by partially esterifying polyhydric aliphatic alcohols with an acids-containing reaction mixture produced by the oxidation of a mixture of petroleum hydrocarbons having a mean carbon chain length falling in the range of C to C which mixture is commonly known as petrolatum or microcrystalline wax. The polyhydric alcohols range in carbon chain length from C to C representative examples being glycerol and sorbitol. :In producing these esters it is preferable that the polyhydric alcohols used in esterifying the acids content of the oxidation reaction mixture be incompletely esterified, i.e., that they retain at least one unreacted hydroxyl group.

The petrolatum or microcrystalline wax is subjected to liquid-phase oxidation as shown in United States Patents Nos. 1,768,523 and 1,828,356 at a temperature of about 140 C., a pressure of about 200 pounds per square inch of air and an air flow of from 250 to 300 cubic feet per minute per 2,000 gallons of wax. The oxidation is continued for approximately 8 hours to produce an oxidate having an acid number of from 23 to 26, a saponification number not in excess of about 75, an ester number of from 44 to 52, and an unoxidized hydrocarbon content of from about 55 to 60 percent. It has been found that thehydrocarbon mixture may be oxidized to the desired acid number and saponification number range in times shorter than 8 hours, for example, in some instances from 6 /2 to 7 hours because of minor variations in the charge material and in the reaction conditions during the oxidation. However, generally an 8-hour oxidation time is required to produce an oxidate having the described desired specifications. The oxidate and the C C polyhydric alcohols are reacted at a temperature of the order of from 140 C. to 200 C. with the heating continued at 200 C. for about 4 hours. The quantity of alcohol employed is calculated so that the esterified mixture will have an acid number of from about 10 to 18 and a saponification number not in excess of 75, generally between 40 and 75. The esterified prodnot has been found to have a flash point of the order of 400 F., and a melting point of the order of F. For the sake of brevity in the description and claims the partial esters produced as has been described will be referred to as partial esters of wax acids. The quantity of partial esters of wax acids in the lubricating oil composition should range from 1.0 volume percent to 5.0

volume percent based on the total volume of the lubricating oil composition. Preferably the quantity of partial esters of wax acids should range from 2.0 to 3.0 volume percent based on the total volume of the composition.

The less efficient water-in-oil emulsifier of this invention is an oil soluble calcium sulfonate. The oil soluble calcium sulfonate may be either the calcium salts of the so-called mahogany sulfonic acids produced by the acid treating of petroleum oils or the calcium salts of high molecular weight synthetic alkyl aryl sulfonic acids with the latter compounds being preferred. The method of production of calcium salts of the petroleum mahogany sulfonic acids is well known and since such compounds and their mode of preparation have been described in numerous patents and in the technical literature and since they are available commercially further description thereof is believed unnecessary.

The oil soluble calcium sulfonates particularly preferred are those produced from the oil soluble sulfonic acids which in turn have been produced by the sulfonation of mixtures of monoand di-alkylated benzenes wherein the alkyl group attached to the benzene nucleus ranges between 22 and 28 carbon atoms in length. The methods of alkylating benzene and the methods of sulfonating the alkylated benzenes are well known and described in patents and technical literature. These preferred oil soluble calcium sulfonates are fluids having an average molecular weight of about 900 and are commercially available as a 30 percent solution in mineral oil. The alkaline calcium sulfonates having a 14 minimum neutralization number (base No. ASTM D-974-52T) are preferred although the neutral sulfonates also may be used. These products are substantially free of inorganic solids and water.

A typical commercial 30 weight percent solution of calcium sulfonate in mineral oil has a specific gravity of 0.93. When in this form the oil soluble calcium sulfonate should range from 1.0 volume percent to 5.0 volume percent based on the total volume of the lubricating oil composition. Expressed in weight percent the oil soluble calcium sulfonate should range from 0.0028 gram to 0.014 gram of calcium sulfonate per milliliter of the total oil composition. Since the oil soluble calcium sulfonate may be supplied in oil solutions of various concentrations, it is preferred to express the quantity of calcium sulfonate in weight percent based on the total oil composition. In such cases, however, it will be understood that the mineral oil in which the calcium sulfonate is contained is considered to be a part of the solvent refined oil ingredient. It is preferred that the volume percent of a commercial 30 weight percent solution of oil soluble calcium sulfonate should range between 2.0 and 3.0 based on the total volume of the lubricating oil composition, or expressed in weight percent, from 0.0056 gram to 0.0084 gram of oil soluble calcium sulfonate per milliliter of the total oil composition.

It is important that the lubricating oil into which the described emulsifiers are blended be of high quality. The most suitable lubricating oil is a solvent refined petroleum lubricating oil having a viscosity from 80 to 2500 Saybolt seconds Universal at 100 F. The most useful lubricating oil base, however, is one having a viscosity ranging from 100 to 300 Saybolt seconds Universal at 100 F. The lubricating oil should range from 91.5 volume percent to 98.5 volume percent of the oil composition prior to emulsification with water. Preferably the oil should range from 93.5 volume percent to 97.5 volume percent. It will be understood that the foregoing volume percent ranges include any small quantities of oil utilized for incorporating other ingredients, for example, the oil of the oil solution of oil soluble calcium sulfonate.

Although it is important that the lubricating oil base be of high quality, present day equipment requires that the oil contain extreme pressure and anti-wear agents. Consequently, it is preferable that the oil contain extreme 4 pressure and anti-wear agents such as from 0.5 to 3.5 volume percent based on the total volume of the oil composition of sulfurized sperm oil and from 0.5 to 3.5 volume percent of an oil solution of lead diamyldithiocarbamate. Preferably the volumes of sulfurized sperm oil and lead diamyldithiocarbamate solution should be equal although other ratios permitted within the critical ranges of these components are completely suitable. The sulfurized sperm oil is preferably the non-corrosive reaction product of sperm oil and elemental sulfur prepared as described in United States Patent No. 2,179,066. The sulfurized sperm oil found to be most suitable for the compositions of this invention contains 10 percent by weight of sulfur, however, this amount is not critical. The lead diamyldithiocarbamate is sold commercially as a 50 weight percent solution in an oil having a viscosity of Saybolt seconds Universal at 100 F. A typical commercial 50 weight percent solution of lead diamyldithiocarbamate in oil has a specific gravity of approximately 1.095. Consequently, with the above-mentioned concentration range of 0.5 volume percent of 3.5 volume percent of the 50 weight percent solution in oil the total oil composition will contain from 0.0027 gram to 0.019 gram of lead diamyldithiocarbamate per milliliter of the oil composition. Since the lead diamyldithiocarbamate may be supplied in oil solutions of various concentrations, it is preferred to express the quantity of lead diamyldithiocarbamate in weight percent based on the total oil composition. In such cases, however, as has been described for the calcium sulfonate solutions, it will be understood that the mineral oil in which the lead diamyldithiocarbamate is contained is considered to be a part of the solvent refined oil ingredient. Falex machine wear tests on the instant lubricating composition have shown that the combination of sulfurized sperm oil and lead diamyldithiocarbamate is superior in load carrying and anti-wear characteristics to either additive alone.

A particularly preferred lubricating oil composition comprises 2.0 volume percent partial esters of wax acids, 1.5 volume percent sulfurized sperm oil, and 96.5 volume percent solvent refined lubricating oil having a viscosity of 100 Saybolt seconds Universal at 100 F., with each milliliter of the oil composition containing 0.0056 gram of oil soluble calcium sulfonate and 0.0082 gram of lead diamyldithiocarbamate.

In addition to the extreme pressure and anti-wear agents, it is sometimes desirable to incorporate into the base oil conventional oxidation inhibitors and rest inhibitors. For example, up to 1 gram of oxidation inhibitor per 100 milliliters of base lubricating oil may be used without disturbing the stability of the emulsions produced from the oil. It has been found that certain combinations of oxidation inhibitors are particularly desirable such as up to 0.5 gram ditertiarybutyl paracresol and up to 0.5 gram of a mixture of octylated and styrenated diphenylamine per 100 milliliters of oil. The octylated and styrenated diphenylamine is sold commercially under the name of Agerite Stalite and is an alkylation mixture produced by the reaction of di-isobutylene, styrene and diphenylarnine in the presence of an aluminum chloride catalyst as disclosed in US. Patent No. 2,530,769 to Arthur T. Hollis. Preferably 0.8 gram of each of these additives per 100 milliliters of oil should be used. Good rust inhibition is obtained without emulsion instability if up to 1.0 volume percent of a conventional rust inhibitor is employed. Smaller quantities of certain rust inhibitors can be employed advantageously, such as up to 0.1 volume percent of the reaction product of di(2-ethylhexyl) amine with a lauryl acid phosphate mixture having a mole ratio of 2 moles of monolauryl acid phosphate to 1 mole of di-lauryl acid phosphate. Preferably 0.03 volume percent of this latter additive should be employed to obtain rust inhibition without harming the other properties of the emulsion produced from the lubricating oil base composition.

The lubricating oil composition of this invention is readily emulsifiable with water. The oil and water can be emulsified with mild stirring, thus it is possible to prepare the emulsions in the field. As the emulsion is used to lubricate gears, pumps, and similar machinery, the oil and water are further emulsified to produce exceedingly stable water-in-oil emulsions.

As has been mentioned the stable emulsions may contain from percent by weight to 95 percent by weight of water. In general, fire resistance is proportional to the water content of the emulsion. ing 40 percent by weight of water or more, adequate fire resistance for hydraulic fluid applications is obtained, however, for certain other purposes water contents ranging from 5 percent to 40 percent by weight provide sulficient fire resistance. When there is from 65 percent to 95 percent by weight of water in the emulsion, the emulsion exhibits a high viscosity, generally at least 1200 Saybolt Seconds Universal at 100 F. This viscosity increases very rapidly as the quantity of water is increased so that at the upper end of the Water content range exceedingly high viscosity emulsions are produced which accordingly have only limited uses.

The emulsions having a water content ranging from 40 percent to 65 percent by Weight have been found to have the greatest utility. These emulsions are particularly useful as fire-resistant hydraulic fluids. Since they contain at least 40 percent by weight of Water they have excellent fire resistance; moreover, since they do not contain more than 65 percent by weight of water, they are sufficiently viscous to lubricate yet fluid enough to feed freely to gears and pumps Without cavitation.

It has been found that for best results the hydraulic fluids should have a viscosity ranging from approximately 100 to 4-00 Saybolt Seconds Universal at operating temperatures which temperatures may range from 100 F. to 180 F. and that such fluids should not have viscosities greatly in excess of 5000 Saybolt Seconds Universal at starting temperatures which may be as low as 40 F. to 50 F. it will be understood that the water phase of the emulsions of this invention may contain freezing point depressants such as methanol, ethanol, ethylene glycol and the like, when the emulsions are exposed to ambient temperatures below the freezing point of the emulsion not containing such depressants in the water phase. For certain uses viscosity ranges broader than the ranges described above may be employed quite effectively.

The lubricating oil compositions of this invention when emulsified with from 40 to 65 weight percent of water produce hydraulic fluids which have viscosities within the desired ranges set forth for hydraulic fluids. The viscosity of the emulsion can be controlled to some extent by the viscosity of the oil composition and also by the quantity of water which is emulsified with the oil.

The fire-resistant emulsions of this invention are characterized by having the water droplets dispersed in the oil uniformly and of a uniformly small size. The diameter of the water droplets should range preferably'between 0.001 inch and 0.0001 inch. This droplet size range produces superior emulsion stability, superior lubrication, lower evaporation tendencies, superior low temperature properties, and more uniform viscosity in service. Emulsion compositions of this invention having uniform water droplets in this droplet size range have been found to be stable for more than three months at room temperatures, i.e. substantially no water or oil separated from the emulsion. in addition, Water droplets in this size range have the ability to pass through filters Without blocking or aggregating. Water droplets larger than approximately 0.001 inch in diameter give emulsions which are unstable and have inferior properties compared with those described above. When the water droplet size is smaller than aproximately 0.0001 inch in diameter the viscosity With emulsions containof the emulsion increases rapidly with the result that it is not always possible to hold the emulsion within the viscosity ranges desired based on the quantity of water contained in the emulsion.

The lubricating oil compositions of this invention are characterized by their ability when emulsified with water to produce emulsions containing water droplets within the aforementioned desired droplet size range of from 0.001 inch to 0.0001 inch.

The following examples are provided for the purpose of illustrating certain specific embodiments of the invention and demonstrating certain critical features of the invention.

The partial esters of wax acids employed in these examples were prepared by the partial esterification with C -C polyhydric alcohols, sorbitol predominating, of the acids-containing reaction mixture produced by the 8-hour liquid phase oxidation of petrolatum as described. The partial esters of the wax acids product had an acid number of 10 and asaponifica-tion number of 54.

The oil soluble calcium sulfonate employed in the examples was prepared from the synthetic monoand dialkyibenzene sulfonic acids wherein the alkyl groups ranged from 22 to 28 carbon atoms in length. The sulfona'te in the fonm of a 30 percent solution in oil had an average molecular Weight of 900, a neutralization number of 14 as measured by the ASTM Method D-974-52T and a specific gravity of 0.93.

The sulfurized sperm oil employed prepared as described herein contained lO weight percent sulfur and the lead diamyldithiocarbamate employed was in the form of the described commercial 50 Weight percent solution in oil which solution had a specific gravity of 1.095.

The solvent refined lubricating oil employed in the exarnples had a viscosity of Saybolt seconds Universal at 100 F. and contained 0.2 gram per 100 milliliters of oil of ditertiary butyl parac-resol, 0.2 gram per 100 milliliters of oil of the described octylated arnd styrenated diphenylamine, and 0.03 volume percent of the reaction product of di(2-ethylhexyl)amine with a lau ryl acid phosphate mixture having a mole ratio of 2 moles of monolauryl acid phosphate to 1 mole of dilauryl acid phosphate.

EXAMPLE I A lubricating oil composition was prepared containing the following ingredients in volume percent based on the total volume of the composition.

Partial esters of wax acids 2.0 Oil soluble calcium sulfonate 2.0 Sulfurized sperm oil 1.5 Lead diamyldithiocarbamate 1.5

Solvent refined lubricating oil 93.0

Portions of this lubricating oil composition were emulsified with various amounts of water and the visoosities of the resultant emulsions determined. Results of these tests are set forth in Table I. it is to be noted that the concentration of the oil soluble calcium sulfonate was 0.0056 gram per milliliter of the oil phase and the concentration of the lead diamyldithiocarbamate was 0.0082 gram per milliliter of the oil phase with the amount of oil excluding the partial esters of wax acids and sulfurized sperm oil being about 96.5 volume percent.

Table I Wt. Percent Viscosity at Emulsion zlggl his emulsion had a viscosity of 300 SSU at F. and SSU at G The droplets of water in the emulsions were of a uniform size and within the range of 0.001 inch to 0.0001 inch in diameter. In the emulsion containing 55 percent by weight of water the droplets were uniformly about 0.0001 inch in diameter.

EXAMPLE II A lubricating oil composition was prepared which was similar to that of Example I except that no calcium sulfonate was employed and the quantity of the partial esters of wax acids was increased such that the emulsifier consisted of 4 volume percent of the partial esters of wax acids only. This composition was emulsified with sufficient water to produce an emulsion containing 55 percent by weight of water. The viscosity of this emulsion was determined and the droplet size of the water droplets in the emulsion was also determined. This emulsion which corresponded to Emulsion No. of Example 1 had a viscosity of 800 Saybolt seconds Universal at 100 F. and contained a mixture of small and large droplets of water, the large droplets of water being greatly in excess of 0.001 inch in diameter. This emulsion in addition to being undesirable because of its exceedingly high viscosity for the quantity of water contained in it, was also unstable because of the mixture of large and small droplets in the emulsion.

EXAMPLE III A lubricating oil composition similar to that of Example I was prepared except that no partial esters of wax acids were employed and the quantity of the oil soluble calcium sulfonate was increased such that the total emulsifier consisted of 4 volume percent of the oil soluble calcium sulfonate only. This composition was emulsified with sufiicent water to produce an emulsion containing 55 percent by weight of water. The viscosity of the emulsion and the droplet size of the water particles of the emulsion were determined. The viscosity was found to be 540 Sayb-olt seconds Universal at 100 F. but the emulsion consisted almost entirely of large droplets of water greatly in excess of 0.001 inch in diameter and hence this emulsion was found to be completely unsuitable and unstable.

EXAMPLE IV An emulsion containing 55 weight percent Water prepared as described for Emulsion No. 5 of Example I was tested in a commercial l-inch gear pump for 500 hours at 1000 pounds per square inch operating pressure and at 150 F. operating temperature. The viscosity of the emulsion after being on test was changed only slightly from that of the fresh emulsion and the water content decreased only 1.1 weight percent. The total pump weight loss was only 0.033 percent demonstrating that the emulsion provided excellent lubrication. The same emulsion was then tested for an additional 500 hours in the gear pump at 1000 pounds per square inch at 190 F. At the end of this test the viscosity of the emulsion had decreased somewhat more than at the end of 500 hours and the water content had decreased to about 51 weignt percent. The total pump weight loss for the 1000-hour test was only 0.18 percent demonstrating that the emulsion retained its excellent lubricating properties when subjected to extremely severe operating conditions.

The flammability of this emulsion was measured by Federal Test Method Standard No. 791-352T, in which a pipe cleaner is soaked in the test fluid, mounted on a windshield wiper motor and passed back and forth through a gas flame until ignition occurs. A large number of cycles indicates a high fire resistance. The solvent refined lubricating oil base material used to prepare the emulsion composition required only 4 cycles for ignition. The fresh emulsion before the gear pump testing, however, required 29 cycles for ignition indicating an excellent fire resistance. After being on test for 1000 hours the emulsion required 26 cycles, demonstrating that it retained its excellent fire resistance.

EXAMPLE V Three lubricating oil compositions were prepared having the following composition expressed in volume percent.

Partial esters of wax acids 2.0 Oil soluble calcium sulfonate 2.0 Sulfurized sperm oil 1.5 Lead diamyldithiocarbamate 1.5

Solvent refined lubricating oil 93.0 Composition No. 3:

Partial esters of wax acids 2.0 Oil soluble calcium sulfonate 2.0 Sulfurized sperm oil 2.5 Lead diamyldithiocarbamate 2.5 Solvent refined lubricating oil 91.0

These emulsions were tested by a modified Falex wear test and extreme pressure test. In the wear test a constant load of 250 pounds was employed and the wear rate in grams per hour on the pins was determined. The wear rate was 0.0336 for the emulsion prepared from Composition No. 1, 0.0070 for the emulsion prepared from Composition No. 2, and 0.0058 for the emulsion prepared from Composition No. 3. In the extreme pressure test the test load was increased by 250-pound increments every 5 minutes. The emulsion prepared from Composition No. 1 failed by seizure in 0.5 minute at 500 pounds load. The emulsion prepared from Composition No. 2 failed by seizure in 0.5 minute at 2,000 pounds load. The emulsion prepared from Composition No. 3 failed by seizure in 2.0 minutes at 2,000 pounds load.

These tests demonstrate the necessity of employing wear inhibiting and extreme pressure additives in the compositions of this invention.

EXAMPLE VI In order to demonstrate the feasibility of producing high water content emulsions from the lubricating oil compositions of this invention, a lubricating oil composition identical to that of Example I was prepared, except that a solvent refined lubricating oil having a viscosity of 2,500 Saybolt seconds Universal at 100 F. was substituted for the solvent refined oil of Example I. This lubricating oil composition was mixed with sufficient water to produce a water-in-oil emulsion containing percent by Weight of water. The resulting emulsion was extremely viscous and had a thick, creamy, paste-like appearance. The water droplet particle size was exceedingly uniform and the emulsion was completely stable.

We claim:

1. A lubricating oil composition suitable for the production of fire-resistant water-in-oil emulsions in which the water phase constitutes from 5 weight percent to 95 weight percent consisting essentially of the following ingredients in volume percent based on the total volume of the oil composition:

Partial esters of wax acids 1.0- 5.0 Sulturized sperm oil 0.5- 3.5 Solvent refined lubricating oil 98.5-91.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range (D -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidatc having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to :18, a sapon-ification number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about 110 F, wherein the solvent refined lubricating oil has a viscosity within the range from 80 to 2500 Saybolt seconds Universal at 100 F, and wherein each milliliter of said oil composition contains from 0.0028 gram to 0.014 gram of a synthetic oil soluble calcium sulfonate having a molecular Weight of about 900 and from 0.0027 gram to 0.019 gram of lead diamyldithiocarbamate.

2. A lubricating oil composition suitable for the production of fire-resistant water-in-oil emulsions in which the water phase constitutes from Weight percent to 95 weight percent consisting essentially of the following ingredients in volume percent based on the total volume of the oil composition:

Partial esters of Wax acids 1.0- 5.0 Sulfurized sperm oil 0.5 3.5 Solvent refined lubricating oil 98.5-91.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular Weight aliphatic carboxylic acids content of an oxidatc of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range C -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponificatiou number of not in excess of about 75 and said reaction product having an acid number in the range from about to 18, a saponitication number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about 110 F., wherein the solvent refined lubricating oil has a viscosity within the range from 100 to 300 Saybolt seconds Universal at 100 F, and wherein each milliliter of said oil composition contains from 0.0028 gram to 0.014 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from 0.0027 gram to 0.019 gram of lead diamyldithioearbamate.

3. A lubricating oil composition suitable for the pro duction of fire-resistant water-in-oil emulsions in which the water phase constitutes from 5 weight percent to 95 weight percent consisting essentially of the following ingredients in volume percent based on the total volume of the oil composition:

Partial esters of wax acids 2.0-3.0 Suliurized sperm oil 0.5-3.5 Solvent refined lubricating oil 97.593.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range (3 -0 subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75', a flash point of about 400 F. and a melting point of about 110 F., wherein the solvent refined lubricating oil has a viscosity within the range from 80 to 2500 Saybolt seconds Universal at 100 5., and wherein each milliliter of said oil composition contains from 0.0056 gram to 0.0084 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from 0.0027 gram to 0.019 gram of lead diamyldithiocarbamate.

4. A lubricating oil composition suitable for the production of fire-resistant water-in-oil emulsions in which the water phase constitutes from 5 weight percent to weight percent consisting essentially of the following ingredients in volume percent based on the total volume of the oil composition:

Partial esters of wax acids 2.03.0 Sulfurized sperm oil 0.5-3.5 Solvent refined lubricating oil 97.5-93.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chai length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxida-te of a petroleum hydrocarbon mixture having a mean carbon chain length falling Within the range (E -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between '40 and 75', a flash point of about 400 F. and a melting point of about 110 F wherein the solvent refined lubricating oil has a viscosity within the range from to 300 Saybol-t seconds Universal at 100 F, and wherein each milliliter of said oil composition contains from 0.0056 gram to 0.0084 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from 0.0027 gram to 0.019 gram of lead diamyldithiocarbamate.

5. A lubricating oil composition suitable for the production of fire-resistant water-in-oil emulsions in which the water phase constitutes from 5 weight percent to 95 weight percent consisting essentially of the following ingredients in volume percent based on the total volume of the oil composition:

Partial esters of wax acids 1.0-5.0 Sulfurized sperm oil 0.53.5 Solvent refined lubricating oil 98.5-91.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxyl-ic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range C -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about F, wherein the solvent refined lubricating oil has a viscosity within the range from 100 to 300 Saybolt seconds Universal at 100 F. and contains up to 1 gram per 100 milliliters of oil of an oxidation inhibitor and up to 1.0 percent by volume of a rust inhibitor, and wherein each milliliter of said oil composition contains from 0.0028 gram to 0.014 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from.0.0027 gram to 0.019 gram of lead diamyldithiocarbamate.

6. A lubricating oil composition suitable for the production of fire-resistant water--in-oil emulsions in which the water phase constitutes from 5 weight percent to 95 weight percent consisting essentially of the following ingredients in volume percent based on the total volume of the oil composition:

Partial esters of wax acids 2.0 Sulfurized sperm oil 1.5 Solvent refined lubricating oil 96.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic a1- cohol having a carbon chain length of from C to C with the high molecular weight miphatic carboxylic acids content of an oxidate or" a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range C C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about '23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about 110 F., wherein the solvent refined lubricating oil has a viscosity of 100 Saybolt seconds Universal at 100 F, and contains 0.2 gram per 100 milliliters of oil of ditertiary butyl paracresol, 0.2 gram per 100 milliliters of oil of octylated and styrenated diphenylamine and 0.03 volume percent of the reaction product of di(2-ethylhexyl) amine with a lauryl acid phosphate mixture having a mole ratio of two moles of mono-lauryl acid phosphate to one mole of dilauryl acid phosphate, and wherein each milliliter of said oil composition contains 0.005 6 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and 0.0082 gram of lead diamyldithiocarbamate.

7. A lubricating oil composition in the form of a water-in-oil emulsion in which the water phase constitutes from 5 weight percent to 95 Weight percent of the emulsion and the oil phase constitutes from 95 Weight percent to 5 weight percent of the emulsion, said oil phase consisting essentially of the following ingredients in volume percent based on the total volume of the oil phase:

Partial esters of wax acids 1.0-5.0 Sulfurized sperm oil O 5-3.5 Solvent refined lubricating oil 98.5-91.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range (I -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about 110 F, wherein the solvent refined lubricating oil has a viscosity within the range from 80 to 2500 Saybolt seconds Universal at 100 F, and wherein each milliliter of said oil phase contains from 0.0028 gram to 0.014 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from 0.0027 gram to 0.019 grant of lead diamyldithiocarbamate.

8. A lubricating oil composition in the form of a water-in-oil emulsion in which the water phase constitutes from 5 weight percent to 95 weight percent of the emulsion and the oil phase constitutes from 95 weight percent to 5 weight percent of the emulsion, said oil phase consisting essentially of the following ingredients in volume percent based on the total volume of the oil phase:

Partial esters of Wax acids 1.0-5.0 Sulfurized sperm oil 0.5-3.5 Solvent refined lubricating oil 98.5-91.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range G -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about 110 F, wherein the solvent refined lubricating oil has a viscosity within the range from 100 to 300 Saybolt seconds Universal at 100 F., and wherein each milliliter of said oil phase contains from 0.0028 gram to 0.014 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from 0.0027 gram to 0.019 gram of lead diamyldithiocarbamate.

9. A lubricating oil composition in the form of a water-in-oil emulsion in which the water phase constitutes from 5 weight percent to 95 Weight percent of the emulsion and the oil phase constitutes from 95 Weight percent to 5 weight percent of the emulsion, said oil phase consisting essentially of the following ingredients in volume percent based on the total volume of the oil phase:

Partial esters of wax acids 2.0-3.0 Sulfurized sperm oil 0.5-3.5 Solvent refined lubricating oil 97.5-93.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range (I -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging etween 40 and 75, a flash point of about 400 F. and a melting point of about 110 1 wherein the solvent refined lubricating oil has a viscosity within the range from to 2500 Saybolt seconds Universal at 100 F., and wherein each milliliter of said oil phase contains from 0.0056 gram to 0.0084 gram of a synthetic oil soluble alcium sulfonate having a molecular Weight of about 900 and from 0.0027 gram to 0.019 gram of lead diamyldithiocarbamate.

10. A lubricating oil composition in the form of a water-in-oil emulsion in which the water phase constitutes from 5 weight percent to weight percent of the emulsion and the oil phase constitutes from 95 weight percent to 5 weight percent of the emulsion, said oil phase consisting essentially of the following ingredients in volume perent based on the total volume of the oil phase:

Partial esters of Wax acids 2.0-3.0 Sulfurized sperm oil 0.5-3.5 Solvent refined lubricating oil 97.5-93.5

wherein the partial esters are the reaction product obtained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range C26-C50 subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 and said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about 110 F., wherein the solvent refined lubricating oil has a viscosity within the range from to 300 Saybolt seconds Universal at 100 F., and

13 wherein each milliliter of said oil phase contains from 0.0065 gram to 0.0084 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from 0.0027 gram to 0.019 gram of lead diamyldithiocarbamate.

11. A fire-resistant hydraulic fluid composition in the form of a water-in-oil emulsion in which the water phase constitutes from 40 weight percent to 65 weight percent of the emulsion and the oil phase constitutes from 60 weight percent to 35 weight percent of the emulsion, said oil phase consisting essentially of the following ingredients in volume percent based on the total volume of the oil phase:

Partial esters of wax acids 1.0-5.0 Sulfurized sperm oil 0.5-3.5 Solvent refined lubricating oil 98.591.5

wherein the partial esters are the reaction product 013- I tained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range U -C subjected to controlled liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about 75 said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75, a flash point of about 400 F. and a melting point of about 110 F., wherein the solvent refined lubricating oil has a viscosity within the range from 100 to 300 Saybolt seconds Universal at 100 F, and wherein each milliliter of said oil phase contains from 0.0028 gram to 0.014 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and from 0.0027 gram to 0.019 gram of lead dia'myldithiocarbamate.

12. A fire-resistant hydraulic fluid composition in the form of a water-in-oil emulsion in which the water phase constitutes from 40 weight percent to 65 weight percent of the emulsion and the oil phase constitutes from 60 weight percent to 35 weight percent of the emulsion, said oil phase consisting essentially of the following ingredients in volume percent based on the total volume of the oil phase:

Partial esters of wax acids 2.0 Sulfurized sperm oil 1.5 Solvent refined lubricating oil 96.5

wherein the partial esters are the reaction product ob tained by partially esterifying a polyhydric aliphatic alcohol having a carbon chain length of from C to C with the high molecular weight aliphatic carboxylic acids content of an oxidate of a petroleum hydrocarbon mixture having a mean carbon chain length falling within the range G -C subjected to control-led liquid-phase partial oxidation for a period of the order of 8 hours said oxidate having an acid number of from about 23 to about 26 and a saponification number of not in excess of about said reaction product having an acid number in the range from about 10 to 18, a saponification number ranging between 40 and 75, a flash point of about 400 and a melting point of about 110 F., wherein the solvent refined lubricating oil has a viscosity of Saybolt seconds Universal at 100 F., and contains 0.2 gram per 100 milliliters of oil of ditertiary butyl paracresol, 0.2 gram per 100 milliliters of oil of octylated and styrenated diphenylamine and 0.03 volume percent of the reaction product of di(2-'ethylhexyl)amine with a lauryl acid phosphate mixture having a mole ratio of two moles of monolauryl acid phosphate to one mole of di-lauryl acid phosphate, and wherein each milliliter of said oil phase contains 0.0056 gram of a synthetic oil soluble calcium sulfonate having a molecular weight of about 900 and 0.0082 gram of lead diamyldithiocarbamate.

References Cited in the file of this patent UNITED STATES PATENTS 2,413,852 Turner Jan. 7, 1947 2,530,769 Hollis Nov. 21, 1950 2,581,132 Nelson et al Jan. 1, 1952 2,710,842 Heisig et al. June 14, 1955 2,907,714 Francis et al Oct. 6, 1959 2,944,021 Ulzheimer et al. July 5, .1960 2,944,022 Ulzheimer et al. July 5, 1960 2,944,023 Kolarik July 5, 1960 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, IOB'OIO October 22, 1963 Harold A. Hartung et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below Column 4, line 21. for "of" second occurrence, read to line 49, for "rest" read rust same column 4 line 63, for "0.8 gram" read 0.2 gram Signed and sealed this 21st day of April 1964.

(SEAL) Allew EDWARD J. BRENNER ERNEST W. SWIDER Attesting Officer Commissioner of Patents 

1. A LUBRICATING OIL COMPOSITION SUITABLE FOR THE PRODUCTION OF FIRE-RESISTANT WATER-IN-OIL EMULSIONS IN WHICH THE WATER PHASE CONSTITUTES FROM 5 WEIGHT PERCENT TO 95 WEIGHT PERCENT CONSISTING ESSENTIALLY OF THE FOLLOWING INGREDIENTS IN VOLUMNE PERCENT BASED ON THE TOTAL VOLUMVE OF THE OIL COMPOSITION: 